Family of multi-speed transmission mechanisms having three planetary gear sets and six torque-transmitting mechanisms

ABSTRACT

The family of transmissions has a plurality of members that can be utilized in powertrains to provide at least seven forward speed ratios and one reverse speed ratio. The transmission family members include three planetary gear sets and six torque transmitting mechanisms. The powertrain includes an engine and torque converter that is continuously connected to at least one member of the planetary gear arrangement and an output member that is continuously connected with another of the planetary gear members. The six torque transmitting mechanisms provide interconnections between various gear members and with the transmission housing, the input or output shaft, in some instances, and are operated in combinations of two to establish at least seven forward speed ratios.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a family of power transmissions havingthree planetary gear sets that are controlled by six torque-transmittingdevices to provide at least seven forward speed ratios and one reversespeed ratio.

2. Background Art

Passenger vehicles include a powertrain that is comprised of an engine,multi-speed transmission, and a differential or final drive. Themulti-speed transmission increases the overall operating range of thevehicle by permitting the engine to operate through its torque range anumber of times. The number of forward speed ratios that are availablein the transmission determines the number of times the engine torquerange is repeated. Early automatic transmissions had two speed ranges.This severely limited the overall speed range of the vehicle andtherefore required a relatively large engine that could produce a widespeed and torque range. This resulted in the engine operating at aspecific fuel consumption point during cruising, other than the mostefficient point. Therefore, manually-shifted (countershafttransmissions) were the most popular.

With the advent of three- and four-speed automatic transmissions, theautomatic shifting (planetary gear) transmission increased in popularitywith the motoring public. These transmissions improved the operatingperformance and fuel economy of the vehicle. The increased number ofspeed ratios reduces the step size between ratios and therefore improvesthe shift quality of the transmission by making the ratio interchangessubstantially imperceptible to the operator under normal vehicleacceleration.

It has been suggested that the number of forward speed ratios beincreased to five and six speeds. This has been accomplished in manyheavy truck powertrains. Six-speed transmissions are disclosed in U.S.Pat. No. 4,070,927 issued to Polak on Jan. 31, 1978; U.S. Pat. No.6,071,208 issued to Koivunen on Jun. 6, 2000; U.S. Pat. No. 5,106,352issued to Lepelletier on Apr. 21, 1992; and U.S. Pat. No. 5,599,251issued to Beim and McCarrick on Feb. 4, 1997.

Six-speed transmissions offer several advantages over four- andfive-speed transmissions, including improved vehicle acceleration andimproved fuel economy. While many trucks employ power transmissions,such as Polak, having six or more forward gear ratios, passenger carsare still manufactured with three- and four-speed automatictransmissions and relatively few five or six-speed devices due to thesize and complexity of these transmissions. The Polak transmissionprovides six forward speed ratios with three planetary gear sets, twoclutches, and three brakes. The Koivunen and Beim patents utilize sixtorque-transmitting devices including four brakes and two clutches toestablish six forward speed ratios and a reverse ratio. The Lepelletierpatent employs three planetary gear sets, three clutches and two brakesto provide six forward speeds. One of the planetary gear sets ispositioned and operated to establish two fixed speed input members forthe remaining two planetary gear sets.

Seven-speed transmissions are disclosed in U.S. Pat. No. 4,709,594 toMaeda; U.S. Pat. No. 6,053,839 to Baldwin et. al.; and U.S. Pat. No.6,083,135 to Baldwin et. al. In addition to further improvements inacceleration and fuel economy, seven- and eight-speed transmissionsprovide an attractive marketing feature. However, like the six-speedtransmissions discussed above, the development of seven- and eight-speedtransmissions has been precluded because of complexity, size and cost.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide an improved familyof transmissions having three planetary gear sets controlled to provideat least seven forward speed ratios.

In one aspect of the present invention, the family of transmissions hasthree planetary gear sets, each of which includes a first, second andthird member, which members may comprise a sun gear, a ring gear, or aplanet carrier assembly member.

In another aspect of the present invention, each of the planetary gearsets may be of the single pinion-type or of the double pinion-type.

In yet another aspect of the present invention, the first member of thefirst planetary gear set is continuously interconnected to the firstmember of the second planetary gear set through a first interconnectingmember.

In still another aspect of the invention, a second interconnectingmember continuously interconnects the second member of the firstplanetary gear set with the first member of the third planetary gearset.

In yet another aspect of the invention, a third interconnecting membercontinuously interconnects the second member of the second planetarygear set with the second member of the third planetary gear set.

In yet a further aspect of the invention, each family memberincorporates an input shaft which is continuously interconnected with atleast one member of the planetary gear sets and an output shaft which iscontinuously connected with another member of the planetary gear sets.

In still a further aspect of the invention, a first torque-transmittingmechanism, such as a brake, selectively interconnects the stationarytransmission housing with a member of the first or second planetary gearsets.

In another aspect of the invention, a second torque-transmittingmechanism, such as a brake, selectively interconnects the stationarytransmission housing with the first, second or third interconnectingmember or a member of the second or third planetary gear sets.

In a still further aspect of the invention, a third torque-transmittingmechanism, such as a brake, selectively interconnects a member of thefirst, second or third planetary gear set with the transmission housing.

In a still further aspect of the invention, a fourth torque-transmittingmechanism, such as a clutch, selectively interconnects a member of thefirst or second planetary gear set with the input shaft, the outputshaft, or another member of the first, second and third planetary gearsets.

In still another aspect of the invention, a fifth torque-transmittingmechanism, such as a clutch, selectively interconnects a member of thesecond or third planetary gear sets with one of the first, second orthird interconnecting members, or another member of the first, second orthird planetary gear sets.

In still another aspect of the invention, a sixth torque-transmittingmechanism, such as a clutch, selectively connects a member of the first,second or third planetary gear sets with another member of the first,second or third planetary gear sets. Alternatively, the sixthtorque-transmitting mechanism is a brake which selectively connects amember of the first, second or third planetary gear sets or one of thefirst, second or third interconnecting members with the transmissionhousing.

In still another aspect of the invention, the six torque-transmittingmechanisms are selectively engageable in combinations of two to yield atleast seven forward speed ratios and one reverse speed ratio.

The above objects and other objects, features, and advantages of thepresent invention are readily apparent from the following detaileddescription of the best modes for carrying out the invention when takenin connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1a is a schematic representation of a powertrain including aplanetary transmission incorporating a family member of the presentinvention;

FIG. 1b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 1a;

FIG. 2a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 2b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 2a;

FIG. 3a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 3b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 3a;

FIG. 4a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 4b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 4a;

FIG. 5a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 5b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 5a;

FIG. 6a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 6b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 6a;

FIG. 7a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 7b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 7a;

FIG. 8a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 8b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 8a;

FIG. 9a is a schematic representation of a powertrain having a planetarytransmission incorporating another family member of the presentinvention;

FIG. 9b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 9a;

FIG. 10a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

FIG. 10b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 10a;

FIG. 11a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

FIG. 11b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 11a;

FIG. 12a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

FIG. 12b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 12a;

FIG. 13a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

FIG. 13b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 13a;

FIG. 14a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

FIG. 14b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 14a;

FIG. 15a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention; and

FIG. 15b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 15a.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings, wherein like characters represent the same orcorresponding parts throughout the several views, there is shown in FIG.1a a powertrain 10 having a conventional engine and torque converter 12,a planetary transmission 14, and a conventional final drive mechanism16.

The planetary transmission 14 includes an input shaft 17 continuouslyconnected with the engine and torque converter 12, a planetary geararrangement 18, and an output shaft 19 continuously connected with thefinal drive mechanism 16. The planetary gear arrangement 18 includesthree planetary gear sets 20, 30 and 40.

The planetary gear set 20 includes a sun gear member 22, a ring gearmember 24, and a planet carrier assembly 26. The planet carrier assembly26 includes a plurality of pinion gears 27 rotatably mounted on acarrier member 29 and disposed in meshing relationship with both the sungear member 22 and the ring gear member 24.

The planetary gear set 30 includes a sun gear member 32, a ring gearmember 34, and a planet carrier assembly member 36. The planet carrierassembly member 36 includes a plurality of pinion gears 37 rotatablymounted on a carrier member 39 and disposed in meshing relationship withboth the sun gear member 32 and the ring gear member 34.

The planetary gear set 40 includes a sun gear member 42, a ring gearmember 44, and a planet carrier assembly member 46. The planet carrierassembly member 46 includes a plurality of pinion gears 47 rotatablymounted on a carrier member 49 and disposed in meshing relationship withboth the sun gear member 42 and the ring gear member 44.

The planetary gear arrangement also includes six torque-transmittingmechanisms 50, 52, 54, 56, 58 and 59. The torque-transmitting mechanisms50, 52 and 54 are stationary-type torque-transmitting mechanisms,commonly termed brakes or reaction clutches. The torque-transmittingmechanisms 56, 58 and 59 are of the rotating-type torque-transmittingmechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member42, and the output shaft 19 is continuously connected with the ring gearmember 24. The planet carrier assembly member 26 is continuouslyconnected with the planet carrier assembly member 36 through theinterconnecting member 70. The sun gear member 22 is continuouslyconnected with the ring gear member 44 through the interconnectingmember 72. The ring gear member 34 is continuously connected with theplanet carrier assembly member 46 through the interconnecting member 74.

The planet carrier assembly member 26 is selectively connectable withthe transmission housing 60 through the brake 50. The ring gear member44 is selectively connectable with the transmission housing 60 throughthe brake 52. The planet carrier assembly member 46 is selectivelyconnectable with the transmission housing 60 through the brake 54. Theplanet carrier assembly member 36 is selectively connectable with thesun gear member 42 through the clutch 56. The sun gear member 32 isselectively connectable with the sun gear member 42 through the clutch58. The sun gear member 42 is selectively connectable with the planetcarrier assembly member 46 through the clutch 59.

As shown in FIG. 1b, and in particular the truth table disclosedtherein, the torque-transmitting mechanisms are selectively engaged incombinations of two to provide seven forward speed ratios and a reversespeed ratio. It should also be noted in the truth table that thetorque-transmitting mechanism 50 remains engaged through a neutralcondition, thereby simplifying the forward/reverse interchange.

The reverse speed ratio is established with the engagement of the brake50 and clutch 59. The brake 50 connects the planet carrier assemblymember 26 to the transmission housing 60, and the clutch 59 connects theplanet carrier assembly member 46 to the sun gear member 42. The sungear member 22 rotates at the same speed as the ring gear member 44. Theplanet carrier assembly members 26 and 36 do not rotate. The ring gearmember 24 rotates at the same speed as the output shaft 19. The ringgear member 24 rotates at a speed determined from the speed of the sungear member 22 and the ring gear/sun gear tooth ratio of the planetarygear set 20. The ring gear member 34, planet carrier assembly member 46,and sun gear member 42 all rotate at the same speed as the input shaft17. The numerical value of the reverse speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set20.

The first forward speed ratio is established with the engagement of thebrakes 50 and 54. The brake 50 connects the planet carrier assemblymember 26 to the transmission housing 60, and the brake 54 connects theplanet carrier assembly member 46 to the transmission housing 60. Thesun gear member 22 rotates at the same speed as the ring gear member 44.The planet carrier assembly members 26 and 36 do not rotate. The ringgear member 24 rotates at the same speed as the output shaft 19. Thering gear member 24 rotates at a speed determined from the speed of thesun gear member 22 and the ring gear/sun gear tooth ratio of theplanetary gear set 20. The ring gear member 34 and planet carrierassembly member 46 also do not rotate. The sun gear member 42 rotates atthe same speed as the input shaft 17. The ring gear member 44 rotates ata speed determined from the speed of the sun gear member 42 and the ringgear/sun gear tooth ratio of the planetary gear set 40. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 20 and 40.

The second forward speed ratio is established with the engagement of thebrake 50 and clutch 58. The brake 50 connects the planet carrierassembly member 26 to the transmission housing 60, and the clutch 58connects the sun gear member 32 to the sun gear member 42. The planetcarrier assembly members 26 and 36 do not rotate. The sun gear member 22rotates at the same speed as the ring gear member 44. The ring gearmember 24 rotates at the same speed as the output shaft 19. The ringgear member 24 rotates at a speed determined from the speed of the sungear member 22 and the ring gear/sun gear tooth ratio of the planetarygear set 20. The ring gear member 34 rotates at the same speed as theplanet carrier assembly member 46. The sun gear members 32 and 42 rotateat the same speed as the input shaft 17. The ring gear member 34 rotatesat a speed determined from the speed of the sun gear member 32 and thering gear/sun gear tooth ratio of the planetary gear set 30. The planetcarrier assembly member 46 rotates at a speed determined from the speedof the ring gear member 44, the speed of the sun gear member 42, and thering gear/sun gear tooth ratio of the planetary gear set 40. Thenumerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets20, 30 and 40.

The third forward speed ratio is established with the engagement of thebrake 54 and the clutch 58. The brake 54 connects the planet carrierassembly member 46 to the transmission housing 60, and the clutch 58connects the sun gear member 32 to the sun gear member 42. The planetcarrier assembly members 26 and 36 rotate at the same speed. The sungear member 22 rotates at the same speed as the ring gear member 44. Thering gear member 24 rotates at the same speed as the output shaft 19.The ring gear member 24 rotates at a speed determined from the speed ofthe planet carrier assembly member 26, the speed of the sun gear member22, and the ring gear/sun gear tooth ratio of the planetary gear set 20.The ring gear member 34 and planet carrier assembly member 46 do notrotate. The sun gear members 32 and 42 rotate at the same speed as theinput shaft 17. The planet carrier assembly member 36 rotates at a speeddetermined from the speed of the sun gear member 32 and the ringgear/sun gear tooth ratio of the planetary gear set 30. The ring gearmember 44 rotates at a speed determined from the speed of the sun gearmember 42 and the ring gear/sun gear tooth ratio of the planetary gearset 40. The numerical value of the third forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 20, 30 and 40.

The fourth forward speed ratio is established with the engagement of thebrake 52 and the clutch 58. The brake 52 connects the ring gear member44 to the transmission housing 60, and the clutch 58 connects the sungear member 32 to the sun gear member 42. The sun gear member 22 andring gear member 44 do not rotate. The planet carrier assembly members26 and 36 rotate at the same speed. The ring gear member 24 rotates atthe same speed as the output shaft 19. The ring gear member 24 rotatesat a speed determined from the speed of the planet carrier assemblymember 26 and the ring gear/sun gear tooth ratio of the planetary gearset 20. The ring gear member 34 rotates at the same speed as the planetcarrier assembly member 46. The sun gear members 32 and 42 rotate at thesame speed as the input shaft 17. The planet carrier assembly member 36rotates at a speed determined from the speed of the ring gear member 34,the speed of the sun gear member 32, and the ring gear/sun gear toothratio of the planetary gear set 30. The planet carrier assembly member46 rotates at a speed determined from the speed of the sun gear member42 and the ring gear/sun gear tooth ratio of the planetary gear set 40.The numerical value of the fourth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets20, 30 and 40.

The fifth forward speed ratio is established with the engagement of theclutches 56 and 58. In this configuration, the input shaft 17 isdirectly connected to the output shaft 19. The numerical value of thefifth forward speed ratio is 1.

The sixth forward speed ratio is established with the engagement of thebrake 52 and the clutch 56. The brake 52 connects the ring gear member44 to the transmission housing 60, and the clutch 56 connects the planetcarrier assembly member 36 to the sun gear member 42. The planet carrierassembly members 26 and 36 and the sun gear member 42 rotate at the samespeed as the input shaft 17. The sun gear member 22 and the ring gearmember 44 do not rotate. The ring gear member 24 rotates at the samespeed as the output shaft 19. The ring gear member 24 rotates at a speeddetermined from the speed of the planet carrier assembly member 26 andthe ring gear/sun gear tooth ratio of the planetary gear set 20. Thering gear member 34 rotates at the same speed as the planet carrierassembly member 46. The numerical value of the sixth forward speed ratiois determined utilizing the ring gear/sun gear tooth ratio of theplanetary gear set 20.

The seventh forward speed ratio is established with the engagement ofthe brake 54 and the clutch 56. The brake 54 connects the planet carrierassembly member 46 to the transmission housing 60, and the clutch 56connects the planet carrier assembly member 36 to the sun gear member42. The planet carrier assembly members 26 and 36 and the sun gearmember 42 rotate at the same speed as the input shaft 17. The sun gearmember 22 rotates at the same speed as the ring gear member 44. The ringgear member 24 rotates at the same speed as the output shaft 19. Thering gear member 24 rotates at a speed determined from the speed of theplanet carrier assembly member 26, the speed of the sun gear member 22,and the ring gear/sun gear tooth ratio of the planetary gear set 20. Thering gear member 34 and planet carrier assembly member 46 do not rotate.The ring gear member 44 rotates at a speed determined from the speed ofthe sun gear member 42 and the ring gear/sun gear tooth ratio of theplanetary gear set 40. The numerical value of the seventh forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 20 and 40.

As set forth above, the engagement schedules for the torque-transmittingmechanisms is shown in the truth table of FIG. 1b. This truth table alsoprovides an example of speed ratios that are available utilizing thering gear/sun gear tooth ratios given by way of example in FIG. 1b. TheR1/S1 value is the tooth ratio of the planetary gear set 20; the R2/S2value is the tooth ratio of the planetary gear set 30; and the R3/S3value is the tooth ratio of the planetary gear set 40. Also, the chartof FIG. 1b describes the ratio steps that are attained utilizing thesample of tooth ratios given. For example, the step ratio between thefirst and second forward speed ratios is 1.91, while the step ratiobetween the reverse and first forward ratio is −0.59. It can also bereadily determined from the truth table of FIG. 1b that all of thesingle step forward ratio interchanges are of the single transitionvariety, as are the double step forward ratio interchanges.

FIG. 2a shows a powertrain 110 having a conventional engine and torqueconverter 12, a planetary transmission 114, and a conventional finaldrive mechanism 16.

The planetary transmission 114 includes an input shaft 17 continuouslyconnected with the engine and torque converter 12, a planetary geararrangement 118, and an output shaft 19 continuously connected with thefinal drive mechanism 16. The planetary gear arrangement 118 includesthree planetary gear sets 120, 130 and 140.

The planetary gear set 120 includes a sun gear member 122, a ring gearmember 124, and a planet carrier assembly 126. The planet carrierassembly 126 includes a plurality of pinion gears 127 rotatably mountedon a carrier member 129 and disposed in meshing relationship with boththe sun gear member 122 and the ring gear member 124.

The planetary gear set 130 includes a sun gear member 132, a ring gearmember 134, and a planet carrier assembly member 136. The planet carrierassembly member 136 includes a plurality of pinion gears 137 rotatablymounted on a carrier member 139 and disposed in meshing relationshipwith both the sun gear member 132 and the ring gear member 134.

The planetary gear set 140 includes a sun gear member 142, a ring gearmember 144, and a planet carrier assembly member 146. The planet carrierassembly member 146 includes a plurality of pinion gears 147 rotatablymounted on a carrier member 149 and disposed in meshing relationshipwith both the sun gear member 142 and the ring gear member 144.

The planetary gear arrangement 118 also includes six torque-transmittingmechanisms 150, 152, 154, 156, 158 and 159. The torque-transmittingmechanisms 150, 152 and 154 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. The torquetransmitting mechanisms 156, 158 and 159 are of the rotating-typetorque-transmitting mechanisms, commonly termed “clutches.”

The input shaft 17 is continuously connected with the sun gear member142, and the output shaft 19 is continuously connected with the ringgear member 124. The sun gear member 122 is continuously connected withthe ring gear member 134 through the interconnecting member 170. Theplanet carrier assembly member 126 is continuously connected with thering gear member 144 through the interconnecting member 172. The sungear member 132 is continuously connected with the sun gear member 142through the interconnecting member 174.

The sun gear member 122 is selectively connectable with the transmissionhousing 160 through the brake 150. The planet carrier assembly member126 is selectively connectable with the transmission housing 160 throughthe brake 152. The planet carrier assembly member 136 is selectivelyconnectable with the transmission housing 160 through the brake 154. Theplanet carrier assembly member 146 is selectively connectable with thering gear member 124 through the clutch 156. The sun gear member 132 isselectively connectable with the planet carrier assembly member 136through the clutch 158. The sun gear member 132 is selectivelyconnectable with the planet carrier assembly member 146 through theclutch 159.

The truth table of FIG. 2b describes the engagement sequence utilized toprovide seven forward speed ratios and a reverse speed ratio in theplanetary gear arrangement 118 shown in FIG. 2a.

The reverse speed ratio is established with the engagement of the brake152 and the clutch 158. The brake 152 connects the planet carrierassembly member 126 to the transmission housing 160, and the clutch 158connects the planet carrier assembly member 136 to the sun gear member132. The planet carrier assembly member 126 and ring gear member 144 donot rotate. The sun gear member 122 rotates at the same speed as thering gear member 134. The ring gear member 124 rotates at the same speedas the output shaft 19. The ring gear member 124 rotates at a speeddetermined from the speed of the sun gear member 122 and the ringgear/sun gear tooth ratio of the planetary gear set 120. The planetcarrier assembly member 136 and the sun gear members 132 and 142 rotateat the same speed as the input shaft 17. The numerical value of thereverse speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 120.

The first forward speed ratio is established with the engagement of thebrakes 152 and 154. The brake 152 connects the planet carrier assemblymember 126 to the transmission housing 160, and the brake 154 connectsthe planet carrier assembly member 136 to the transmission housing 160.The planet carrier assembly member 126 and ring gear member 144 do notrotate. The sun gear member 122 rotates at the same speed as the ringgear member 134. The ring gear member 124 rotates at the same speed asthe output shaft 19. The ring gear member 124 rotates at a speeddetermined from the speed of the sun gear member 122 and the ringgear/sun gear tooth ratio of the planetary gear set 120. The planetcarrier assembly member 136 does not rotate. The sun gear members 132and 142 rotate at the same speed as the input shaft 17. The ring gearmember 134 rotates at a speed determined from the speed of the sun gearmember 132 and the ring gear/sun gear tooth ratio of the planetary gearset 130. The numerical value of the first forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 120 and 130.

The second forward speed ratio is established with the engagement of thebrake 152 and the clutch 156. The brake 152 connects the planet carrierassembly member 126 to the transmission housing 160, and the clutch 156connects the ring gear member 124 to the planet carrier assembly member146. The planet carrier assembly member 126 and ring gear member 144 donot rotate. The sun gear member 122 rotates at the same speed as thering gear member 134. The sun gear members 132 and 142 rotate at thesame speed as the input shaft 17. The planet carrier assembly member 146rotates at the same speed as the ring gear member 124 and the outputshaft 19. The planet carrier assembly member 146 rotates at a speeddetermined from the speed of the sun gear member 142 and the ringgear/sun gear tooth ratio of the planetary gear set 140. The numericalvalue of the second forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 140.

The third forward speed ratio is established with the engagement of thebrake 154 and the clutch 156. The brake 154 connects the planet carrierassembly member 136 to the transmission housing 160, and the clutch 156connects the ring gear member 124 to the planet carrier assembly member146. The sun gear member 122 rotates at the same speed as the ring gearmember 134. The planet carrier assembly member 126 rotates at the samespeed as the ring gear member 144. The ring gear member 124 rotates atthe same speed as the planet carrier assembly member 146 and the outputshaft 19. The ring gear member 124 rotates at a speed determined fromthe speed of the sun gear member 122, the speed of the planet carrierassembly member 146, and the ring gear/sun gear tooth ratio of theplanetary gear set 120. The planet carrier assembly member 136 does notrotate. The sun gear members 132 and 142 rotate at the same speed as theinput shaft 17. The ring gear member 134 rotates at a speed determinedfrom the speed of the sun gear member 132 and the ring gear/sun geartooth ratio of the planetary gear set 130. The planet carrier assemblymember 146 rotates at a speed determined from the speed of the ring gearmember 144, the speed of the sun gear member 142, and the ring gear/sungear tooth ratio of the planetary gear set 140. The numerical value ofthe third forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 120, 130 and 140.

The fourth forward speed ratio is established with the engagement of thebrake 150 and the clutch 156. The brake 150 connects the sun gear member122 to the transmission housing 160, and the clutch 156 connects thering gear member 124 to the planet carrier assembly member 146. The sungear member 122 and ring gear member 134 do not rotate. The planetcarrier assembly member 126 rotates at the same speed as the ring gearmember 144. The ring gear member 124 rotates at the same speed as theplanet carrier assembly member 146 and the output shaft 19. The ringgear member 124 rotates at a speed determined from the speed of theplanet carrier assembly member 126, and the ring gear/sun gear toothratio of the planetary gear set 120. The sun gear members 132 and 142rotate at the same speed as the input shaft 17. The planet carrierassembly member 146 rotates at a speed determined from the speed of thering gear member 144, the speed of the sun gear member 142, and the ringgear/sun gear tooth ratio of the planetary gear set 140. The numericalvalue of the fourth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 120 and 140.

The fifth forward speed ratio is established with the engagement of theclutches 156 and 159. In this configuration, the input shaft 17 isdirectly connected to the output shaft 19. The numerical value of thefifth forward speed ratio is 1.

The sixth forward speed ratio is established with the engagement of thebrake 150 and the clutch 159. The brake 150 connects the sun gear member122 to the transmission housing 160. The clutch 159 connects the planetcarrier assembly member 146 to the sun gear member 142. The sun gearmember 122 and ring gear member 134 do not rotate. The planet carrierassembly member 126 rotates at the same speed as the ring gear member144. The ring gear member 124 rotates at the same speed as the outputshaft 19. The ring gear member 124 rotates at a speed determined fromthe speed of the planet carrier assembly member 126, and the ringgear/sun gear tooth ratio of the planetary gear set 120. The planetcarrier assembly member 146 and the sun gear members 132 and 142 rotateat the same speed as the input shaft 17. The numerical value of thesixth forward speed ratio is determined utilizing the ring gear/sun geartooth ratio of the planetary gear set 120.

The seventh forward speed ratio is established with the engagement ofthe brake 154 and the clutch 159. The brake 154 connects the planetcarrier assembly member 136 to the transmission housing 160, and theclutch 159 connects the planet carrier assembly member 146 to the sungear member 142. The sun gear member 122 rotates at the same speed asthe ring gear member 134. The planet carrier assembly member 126 rotatesat the same speed as the ring gear member 144. The ring gear member 124rotates at the same speed as the output shaft 19. The ring gear member124 rotates at a speed determined from the speed of the planet carrierassembly member 126, the speed of the sun gear member 122, and the ringgear/sun gear tooth ratio of the planetary gear set 120. The planetcarrier assembly member 136 does not rotate. The sun gear members 132and 142 and the planet carrier assembly member 146 rotate at the samespeed as the input shaft 17. The ring gear member 134 rotates at a speeddetermined from the speed of the sun gear member 132 and the ringgear/sun gear tooth ratio of the planetary gear set 130. The numericalvalue of the seventh forward speed ratio is determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 120 and 130.

As set forth above, the truth table of FIG. 2b describes the engagementsequence of the torque-transmitting mechanisms utilized to provide areverse drive ratio and seven forward speed ratios. It can be readilydetermined from the truth table that all of the single step forwardinterchanges are of the single transition type, as are the double stepforward interchanges. The truth table also provides an example of theratios that can be attained with the family members shown in FIG. 2autilizing the sample tooth ratios given in FIG. 2b. The R1/S1 value isthe tooth ratio of the planetary gear set 120; the R2/S2 value is thetooth ratio of the planetary gear set 130; and the R3/S3 value is thetooth ratio of the planetary gear set 140. Also shown in FIG. 2b are theratio steps between single step ratios in the forward direction as wellas the reverse to first ratio step ratio. For example, the first tosecond step ratio is 1.79.

Turning to FIG. 3a, a powertrain 210 includes the engine and torqueconverter 12, a planetary transmission 214, and a final drive mechanism16. The planetary transmission 214 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 218, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 218 includes three planetary gear sets 220, 230 and 240.

The planetary gear set 220 includes a sun gear member 222, a ring gearmember 224, and a planet carrier assembly 226. The planet carrierassembly 226 includes a plurality of pinion gears 227 rotatably mountedon a carrier member 229 and disposed in meshing relationship with boththe sun gear member 222 and the ring gear member 224.

The planetary gear set 230 includes a sun gear member 232, a ring gearmember 234, and a planet carrier assembly member 236. The planet carrierassembly member 236 includes a plurality of pinion gears 237 rotatablymounted on a carrier member 239 and disposed in meshing relationshipwith both the sun gear member 232 and the ring gear member 234.

The planetary gear set 240 includes a sun gear member 242, a ring gearmember 244, and a planet carrier assembly member 246. The planet carrierassembly member 246 includes a plurality of pinion gears 247 rotatablymounted on a carrier member 249 and disposed in meshing relationshipwith both the sun gear member 242 and the ring gear member 244.

The planetary gear arrangement 218 also includes six torque-transmittingmechanisms 250, 252, 254, 256, 258 and 259. The torque-transmittingmechanisms 250, 252 and 254 are stationary type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 256, 258 and 259 are of the rotating typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member242, and the output shaft 19 is continuously connected with the ringgear member 224. The sun gear member 222 is continuously connected withthe ring gear member 234 through the interconnecting member 270. Theplanet carrier assembly member 226 is continuously connected with theplanet carrier assembly member 246 through the interconnecting member272. The sun gear member 232 is continuously connected with the sun gearmember 242 through the interconnecting member 274.

The sun gear member 222 is selectively connectable with the transmissionhousing 260 through the brake 250. The planet carrier assembly member226 is selectively connectable with the transmission housing 260 throughthe brake 252. The planet carrier assembly member 236 is selectivelyconnectable with the transmission housing 260 through the brake 254. Thesun gear member 232 is selectively connectable with the planet carrierassembly member 246 through the clutch 256. The sun gear member 232 isselectively connectable with the planet carrier assembly member 236through the clutch 258. The planet carrier assembly member 236 isselectively connectable with the ring gear member 244 through the clutch259.

As shown in the truth table in FIG. 3b, the torque-transmittingmechanisms are engaged in combinations of two to establish seven forwardspeed ratios and one reverse ratio.

The reverse speed ratio is established with the engagement of the brake252 and the clutch 258. The brake 252 connects the planet carrierassembly member 226 to the transmission housing 260, and the clutch 258connects the planet carrier assembly member 236 to the sun gear member232. The planet carrier assembly members 226 and 246 do not rotate. Thesun gear member 222 rotates at the same speed as the ring gear member234. The ring gear member 224 rotates at the same speed as the outputshaft 19. The ring gear member 224 rotates at a speed determined fromthe speed of the sun gear member 222 and the ring gear/sun gear toothratio of the planetary gear set 220. The planet carrier assembly member236 and the sun gear members 232 and 242 rotate at the same speed as theinput shaft 17. The numerical value of the reverse speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 220.

The first forward speed ratio is established with the engagement of thebrakes 252 and 254. The brake 252 connects the planet carrier assemblymember 226 to the transmission housing 260, and the brake 254 connectsthe planet carrier assembly member 236 to the transmission housing 260.The sun gear member 222 rotates at the same speed as the ring gearmember 234. The ring gear member 224 rotates at a speed determined fromthe speed of the sun gear member 222 and the ring gear/sun gear toothratio of the planetary gear set 220. The planet carrier assembly member236 does not rotate. The sun gear members 232 and 242 rotate at the samespeed as the input shaft 17. The ring gear member 234 rotates at a speeddetermined from the speed of the sun gear member 232 and the ringgear/sun gear tooth ratio of the planetary gear set 230. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 220 and 230.

The second forward speed ratio is established with the engagement of thebrake 252 and the clutch 259. The brake 252 connects the planet carrierassembly member 226 to the transmission housing 260, and the clutch 259connects the planet carrier assembly member 236 to the ring gear member244. The planet carrier assembly members 226 and 246 do not rotate. Thesun gear member 222 rotates at the same speed as the ring gear member234. The ring gear member 224 rotates at the same speed as the outputshaft 19. The ring gear member 224 rotates at a speed determined fromthe speed of the sun gear member 222 and the ring gear/sun gear toothratio of the planetary gear set 220. The planet carrier assembly member236 rotates at the same speed as the ring gear member 244. The sun gearmembers 232 and 242 rotate at the same speed as the input shaft 17. Theplanet carrier assembly member 236 rotates at a speed determined fromthe speed of the ring gear member 234, the speed of the sun gear member232, and the ring gear/sun gear tooth ratio of the planetary gear set230. The ring gear member 244 rotates at a speed determined from thespeed of the sun gear member 242 and the ring gear/sun gear tooth ratioof the planetary gear set 240. The numerical value of the second forwardspeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 220, 230 and 240.

The third forward speed ratio is established with the engagement of thebrake 254 and the clutch 259. The brake 254 connects the ring gearmember 236 to the transmission housing 260, and the clutch 259 connectsthe planet carrier assembly member 236 to the ring gear member 244. Thesun gear member 222 rotates at the same speed as the ring gear member234. The planet carrier assembly member 226 rotates at the same speed asthe planet carrier assembly member 246. The ring gear member 224 rotatesat the same speed as the output shaft 19. The ring gear member 224rotates at a speed determined from the speed of the planet carrierassembly member 226, the speed of the sun gear member 222, and the ringgear/sun gear tooth ratio of the planetary gear set 220. The planetcarrier assembly member 236 and ring gear member 244 do not rotate. Thesun gear members 232 and 242 rotate at the same speed as the input shaft17. The ring gear member 234 rotates at a speed determined from thespeed of the sun gear member 232 and the ring gear/sun gear tooth ratioof the planetary gear set 230. The planet carrier assembly member 246rotates at a speed determined from the speed of the sun gear member 242and the ring gear/sun gear tooth ratio of the planetary gear set 240.The numerical value of the third forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets220, 230 and 240.

The fourth forward speed ratio is established with the engagement of thebrake 250 and the clutch 259. The brake 250 connects the sun gear member222 to the transmission housing 260, and the clutch 259 connects theplanet carrier assembly member 236 to the ring gear member 244. The sungear member 222 and the ring gear member 234 do not rotate. The planetcarrier assembly members 226 and 246 rotate at the same speed. The ringgear member 224 rotates at the same speed as the output shaft 19. Thespeed of the ring gear member 224 is determined from the speed of theplanet carrier assembly member 226 and the ring gear/sun gear toothratio of the planetary gear set 220. The planet carrier assembly member236 rotates at the same speed as the ring gear member 244. The sun gearmembers 232 and 242 rotate at the same speed as the input shaft 17. Thespeed of the planet carrier assembly member 236 is determined from thespeed of the sun gear member 232 and the ring gear/sun gear tooth ratioof the planetary gear set 230. The planet carrier assembly member 246rotates at a speed determined from the speed of the ring gear member244, the speed of the sun gear member 242, and the ring gear/sun geartooth ratio of the planetary gear set 240. The numerical value of thefourth forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 220, 230 and 240.

The fifth forward speed ratio is established with the engagement of theclutches 256 and 259. In this configuration, the input shaft 17 isdirectly connected to the output shaft 19. The numerical value of thefifth forward speed ratio is 1.

The sixth forward speed ratio is established with the engagement of thebrake 250 and the clutch 256. The brake 250 connects the sun gear member222 to the transmission housing 260, and the clutch 256 connects theplanet carrier assembly member 246 to the sun gear member 242. The sungear member 222 and ring gear member 234 do not rotate. The planetcarrier assembly member 226 rotates at the same speed as the planetcarrier assembly member 246, the sun gear members 232 and 242, and theinput shaft 17. The ring gear member 224 rotates at the same speed asthe output shaft 19. The ring gear member 224 rotates at a speeddetermined from the speed of the planet carrier assembly member 226 andthe ring gear/sun gear tooth ratio of the planetary gear set 220. Thenumerical value of the sixth forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 220.

The seventh forward speed ratio is established with the engagement ofthe brake 254 and the clutch 256. The brake 254 connects the planetcarrier assembly member 236 to the transmission housing 260, and theclutch 256 connects the planet carrier assembly member 246 to the sungear member 242. The sun gear member 222 rotates at the same speed asthe ring gear member 234. The planet carrier assembly member 226 rotatesat the same speed as the planet carrier assembly member 246, the sungear members 232 and 242, and the input shaft 17. The ring gear member224 rotates at the same speed as the output shaft 19. The ring gearmember 224 rotates at a speed determined from the speed of the planetcarrier assembly member 226, the speed of the sun gear member 222, andthe ring gear/sun gear tooth ratio of the planetary gear set 220. Thering gear member 234 rotates at a speed determined from the speed of thesun gear member 232 and the ring gear/sun gear tooth ratio of theplanetary gear set 230. The numerical value of the seventh forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 220 and 230.

As previously set forth, the truth table of FIG. 3b describes thecombinations of engagements utilized for the seven forward speed ratiosand reverse ratio. The truth table also provides an example of speedratios that are available with the family member described above. Theseexamples of speed ratios are determined utilizing the tooth ratios givenin FIG. 3b. The R1/S1 value is the tooth ratio of the planetary gear set220; the R2/S2 value is the tooth ratio of the planetary gear set 230;and the R3/S3 value is the tooth ratio of the planetary gear set 240.Also depicted in FIG. 3b is a chart representing the ratio steps betweenadjacent forward speed ratios and the reverse speed ratio. For example,the first to second ratio interchange has a step of 1.95. It can also bereadily determined from the truth table of FIG. 3b that all of thesingle step forward ratio interchanges are of the single transitionvariety, as are all of the double step forward interchanges.

A powertrain 310, shown in FIG. 4a, includes the engine and torqueconverter 12, a planetary transmission 314, and the final drivemechanism 16. The planetary transmission 314 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 318, and output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 318 includes three planetary gear sets 320, 330 and 340.

The planetary gear set 320 includes a sun gear member 322, a ring gearmember 324, and a planet carrier assembly member 326. The planet carrierassembly member 326 includes a plurality of pinion gears 327 rotatablymounted on a carrier member 329 and disposed in meshing relationshipwith both the sun gear member 322 and the ring gear member 324.

The planetary gear set 330 includes a sun gear member 332, a ring gearmember 334, and a planet carrier assembly member 336. The planet carrierassembly member 336 includes a plurality of pinion gears 337 rotatablymounted on a carrier member 339 and disposed in meshing relationshipwith both the sun gear member 332 and the ring gear member 334.

The planetary gear set 340 includes a sun gear member 342, a ring gearmember 344, and a planet carrier assembly member 346. The planet carrierassembly member 346 includes a plurality of pinion gears 347 rotatablymounted on a carrier member 349 and disposed in meshing relationshipwith both the sun gear member 342 and the ring gear member 344.

The planetary gear arrangement 318 also includes six torque-transmittingmechanisms 350, 352, 354, 356, 358 and 359. The torque-transmittingmechanisms 350, 352 and 354 are stationary type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 356, 358 and 359 are of the rotating typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member332, and the output shaft 19 is continuously connected with the ringgear member 344. The ring gear member 324 is continuously connected withthe planet carrier assembly member 336 through the interconnectingmember 370. The planet carrier assembly member 326 is continuouslyconnected with the planet carrier assembly member 346 through theinterconnecting member 372. The ring gear member 334 is continuouslyconnected with the sun gear member 342 through the interconnectingmember 374.

The planet carrier assembly member 336 is selectively connectable withthe transmission housing 360 through the brake 350. The planet carrierassembly member 346 is selectively connectable with the transmissionhousing 360 through the brake 352. The sun gear member 342 isselectively connectable with the transmission housing 360 through thebrake 354. The planet carrier assembly member 336 is selectivelyconnectable with the sun gear member 332 through the clutch 356. Theplanet carrier assembly member 326 is selectively connectable with thesun gear member 332 through the clutch 358. The sun gear member 322 isselectively connectable with the sun gear member 332 through the clutch359.

The truth tables given in FIGS. 4b, 5 b, 6 b, 7 b, 8 b, 9 b, 10 b, 11 b,12 b, 13 b, 14 b and 15 b show the engagement sequences for thetorque-transmitting mechanisms to provide at least seven forward speedratios and one reverse ratio. As shown and described above for theconfiguration in FIGS. 1a, 2 a and 3 a, those skilled in the art willunderstand from the respective truth tables how the speed ratios areestablished through the planetary gear sets identified in the writtendescription.

The truth table shown in FIG. 4b describes the engagement combinationand the engagement sequence necessary to provide the reverse drive ratioand seven forward speed ratios. A sample of the numerical values for theratios is also provided in the truth table of FIG. 4b. These values aredetermined utilizing the ring gear/sun gear tooth ratios also given inFIG. 4b. The R1/S1 value is the tooth ratio for the planetary gear set320; the R2/S2 value is the tooth ratio for the planetary gear set 330;and the R3/S3 value is the tooth ratio for the planetary gear set 340.Also given in FIG. 4b is a chart describing the step ratios between theadjacent forward speed ratios and the reverse to first forward speedratio. For example, the first to second forward speed ratio step is1.95. It can be readily determined from the truth table of FIG. 4b thateach of the forward single step ratio interchanges is a singletransition shift, as are the double step interchanges. The chart alsoshows that the torque-transmitting mechanism 352 can be engaged throughthe neutral condition to simplify the forward/reverse interchange.

Those skilled in the art will recognize that the numerical values of thereverse and sixth forward speed ratios are determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 340. The numericalvalues of the first and seventh forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets330 and 340. The numerical values of the second, third and fourthforward speed ratios are determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 320, 330 and 340. The numericalvalue of the fifth forward speed ratio is 1.

A powertrain 410, shown in FIG. 5a, includes the engine and torqueconverter 12, a planetary transmission 414 and the final drive mechanism16. The planetary transmission 414 includes a planetary gear arrangement418, input shaft 17 and output shaft 19. The planetary gear arrangement418 includes three simple planetary gear sets 420, 430 and 440.

The planetary gear set 420 includes a sun gear member 422, a ring gearmember 424, and a planet carrier assembly 426. The planet carrierassembly 426 includes a plurality of pinion gears 427 rotatably mountedon a carrier member 429 and disposed in meshing relationship with boththe sun gear member 422 and the ring gear member 424.

The planetary gear set 430 includes a sun gear member 432, a ring gearmember 434, and a planet carrier assembly member 436. The planet carrierassembly member 436 includes a plurality of pinion gears 437 rotatablymounted on a carrier member 439 and disposed in meshing relationshipwith both the sun gear member 432 and the ring gear member 434.

The planetary gear set 440 includes a sun gear member 442, a ring gearmember 444, and a planet carrier assembly member 446. The planet carrierassembly member 446 includes a plurality of pinion gears 447 rotatablymounted on a carrier member 449 and disposed in meshing relationshipwith both the sun gear member 442 and the ring gear member 444.

The planetary gear arrangement 418 also includes six torque-transmittingmechanisms 450, 452, 454, 456, 458 and 459. The torque-transmittingmechanisms 450, 452 and 454 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 456, 458 and 459 are of the rotating-typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member442, and the output shaft 19 is continuously connected with the ringgear member 424. The planet carrier assembly member 426 is continuouslyconnected with the ring gear member 434 through the interconnectingmember 470. The sun gear member 422 is continuously connected with thering gear member 444 through the interconnecting member 472. The sungear member 432 is continuously connected with the sun gear member 442through the interconnecting member 474.

The planet carrier assembly member 426 is selectively connectable withthe transmission housing 460 through the brake 450. The ring gear member444 is selectively connectable with the transmission housing 460 throughthe brake 452. The planet carrier assembly member 446 is selectivelyconnectable with the transmission housing 460 through the brake 454. Thering gear member 424 is selectively connectable with the planet carrierassembly member 436 through the clutch 456. The sun gear member 432 isselectively connectable with the planet carrier assembly member 436through the clutch 458. The sun gear member 442 is selectivelyconnectable with the planet carrier assembly member 446 through theclutch 459.

The truth table shown in FIG. 5b describes the engagement combinationand sequence of the torque-transmitting mechanisms 450, 452, 454, 456,458 and 459 that are employed to provide the reverse drive ratio and theseven forward speed ratios. It should be noted that thetorque-transmitting mechanism 450 is engaged through the neutralcondition to simplify the forward/reverse interchange.

Also given in the truth table of FIG. 5b is a set of numerical valuesthat are attainable with the present invention utilizing the ringgear/sun gear tooth ratios shown. The R1/S1 value is the tooth ratio ofthe planetary gear set 420; the R2/S2 value is the tooth ratio of theplanetary gear set 430; and the R3/S3 value is the tooth ratio of theplanetary gear set 440. As can also be determined from the truth tableof FIG. 5b, the single step forward interchanges are single transitionshifts, as are the double step interchanges in the forward direction.

FIG. 5b also provides a chart of the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is1,94. Those skilled in the art will recognize that the numerical valuesof the reverse and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 420. Thenumerical values of the first and seventh forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 420 and 440. The numerical value of the secondforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 430. The numerical value of the thirdforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 420, 430 and 440. The numerical valueof the fourth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 420 and 430. Thenumerical value of the fifth forward speed ratio is 1.

A powertrain 510, shown in FIG. 6a, includes an engine and torqueconverter 12, a planetary gear transmission 514 and the final drivemechanism 16. The planetary transmission 514 includes the input shaft17, a planetary gear arrangement 518 and the output shaft 19. Theplanetary gear arrangement 518 includes three planetary gear sets 520,530 and 540.

The planetary gear set 520 includes a sun gear member 522, a ring gearmember 524, and a planet carrier assembly 526. The planet carrierassembly 526 includes a plurality of pinion gears 527 rotatably mountedon a carrier member 529 and disposed in meshing relationship with boththe sun gear member 522 and the ring gear member 524.

The planetary gear set 530 includes a sun gear member 532, a ring gearmember 534, and a planet carrier assembly member 536. The planet carrierassembly member 536 includes a plurality of pinion gears 537 rotatablymounted on a carrier member 539 and disposed in meshing relationshipwith both the sun gear member 532 and the ring gear member 534.

The planetary gear set 540 includes a sun gear member 542, a ring gearmember 544, and a planet carrier assembly member 546. The planet carrierassembly member 546 includes a plurality of pinion gears 547 rotatablymounted on a carrier member 549 and disposed in meshing relationshipwith both the sun gear member 542 and the ring gear member 544.

The planetary gear arrangement 518 also includes six torque-transmittingmechanisms 550, 552, 554, 556, 558 and 559. The torque-transmittingmechanisms 550, 552 and 554 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 556, 558 and 559 are rotating-typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member542, and the output shaft 19 is continuously connected with the planetcarrier assembly member 526. The planet carrier assembly member 526 iscontinuously connected with the ring gear member 534 through theinterconnecting member 570. The sun gear member 522 is continuouslyconnected with the sun gear member 542 through the interconnectingmember 572. The sun gear member 532 is continuously connected with thering gear member 544 through the interconnecting member 574.

The planet carrier assembly member 536 is selectively connectable withthe transmission housing 560 through the brake 550. The ring gear member544 is selectively connectable with the transmission housing 560 throughthe brake 552. The planet carrier assembly member 546 is selectivelyconnectable with the transmission housing 560 through the clutch 554.The planet carrier assembly member 536 is selectively connectable withthe sun gear member 542 through the clutch 556. The sun gear member 542is selectively connectable with the planet carrier assembly member 546through the clutch 558. The ring gear member 524 is selectivelyconnectable with the planet carrier assembly member 536 through theclutch 559.

The truth table shown in FIG. 6b describes the engagement sequence andcombination of the torque-transmitting mechanisms to provide the reversespeed ratio and seven forward speed ratios. It should be noted that thetorque-transmitting mechanism 550 can remain engaged through the neutralcondition, thereby simplifying the forward/reverse interchange. It canalso be determined from the truth table of FIG. 6b that all of thesingle step forward ratio interchanges are of the single transitionvariety, as are all of the double step forward interchanges. The chartof FIG. 6b describes the ratio steps between adjacent forward speedratios and the ratio step between the reverse and first forward speedratio.

Those skilled in the art, upon reviewing the truth table and theschematic representation of FIG. 6a, can determine that the numericalvalues of the reverse and sixth forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set530. The numerical values of the first and seventh forward speed ratiosare determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 530 and 540. The numerical value of the secondforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 520. The numerical value of the thirdforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 520, 530 and 540. The numerical valueof the fourth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 520 and 530. Thenumerical value of the fifth forward speed ratio is 1.

The sample speed ratios given in the truth table are determinedutilizing the tooth ratio values also given in FIG. 6b. The R1/S1 valueis the tooth ratio of the planetary gear set 520; the R2/S2 value is thetooth ratio of the planetary gear set 530; and the R3/S3 value is thetooth ratio of the planetary gear set 540.

A powertrain 610, shown in FIG. 7a, has the engine and torque converter12, a planetary transmission 614 and the final drive mechanism 16. Theplanetary transmission 614 includes the input shaft 17, a planetary geararrangement 618 and the output shaft 19. The planetary gear arrangement618 includes three planetary gear sets 620, 630 and 640.

The planetary gear set 620 includes a sun gear member 622, a ring gearmember 624, and a planet carrier assembly 626. The planet carrierassembly 626 includes a plurality of pinion gears 627 rotatably mountedon a carrier member 629 and disposed in meshing relationship with boththe sun gear member 622 and the ring gear member 624.

The planetary gear set 630 includes a sun gear member 632, a ring gearmember 634, and a planet carrier assembly member 636. The planet carrierassembly member 636 includes a plurality of pinion gears 637 rotatablymounted on a carrier member 639 and disposed in meshing relationshipwith both the sun gear member 632 and the ring gear member 634.

The planetary gear set 640 includes a sun gear member 642, a ring gearmember 644, and a planet carrier assembly member 646. The planet carrierassembly member 646 includes a plurality of pinion gears 647 rotatablymounted on a carrier member 649 and disposed in meshing relationshipwith both the sun gear member 642 and the ring gear member 644.

The planetary gear arrangement 618 also includes six torque-transmittingmechanisms 650, 652, 654, 656, 658 and 659. The torque-transmittingmechanisms 650, 652, 654 and 656 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 658 and 659 are of the rotating-typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 646, and the output shaft 19 is continuously connectedwith the ring gear member 624. The sun gear member 622 is continuouslyconnected with the ring gear member 634 through the interconnectingmember 670. The planet carrier assembly member 626 is continuouslyconnected with the ring gear member 644 through the interconnectingmember 672. The sun gear member 632 is continuously connected with theplanet carrier assembly member 646 through the interconnecting member674.

The ring gear member 634 is selectively connectable with thetransmission housing 660 through the brake 650. The planet carrierassembly member 626 is selectively connectable with the transmissionhousing 660 through the brake 652. The planet carrier assembly member636 is selectively connectable with the transmission housing 660 throughthe brake 654. The sun gear member 642 is selectively connectable withthe transmission housing 660 through the brake 656. The planet carrierassembly member 636 is selectively connectable with the ring gear member644 through the clutch 658. The sun gear member 632 is selectivelyconnectable with the planet carrier assembly member 636 through theclutch 659.

The truth table shown in FIG. 7b describes the combination oftorque-transmitting mechanism engagements that will provide the reversedrive ratio and seven forward speed ratios, as well as the sequence ofthese engagements and interchanges. The torque-transmitting mechanism652 can be engaged through the neutral condition, thereby simplifyingthe forward/reverse interchange. It can be noted from the truth tablethat each of the single step forward interchanges are single transitionratio changes, as are the double step forward interchanges.

The ratio values given are by way of example and are establishedutilizing the ring gear/sun gear tooth ratios given in FIG. 7b. Forexample, the R1/S1 value is the tooth ratio of the planetary gear set620; the R2/S2 value is the tooth ratio of the planetary gear set 630;and the R3/S3 value is the tooth ratio of the planetary gear set 640.The ratio steps between adjacent forward ratios and the reverse to firstratio are also given in FIG. 7b.

Those skilled in the art will, upon reviewing the truth table of FIG.7b, recognize that the numerical value of the reverse speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 620. The numerical values of the first and second forward speedratios are determined utilizing the ring gear/sun gear tooth ratios ofthe planetary gear sets 620 and 630. The numerical value of the thirdforward speed ratio is 1. The numerical values of the fourth and seventhforward speed ratios are determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 620, 630 and 640. The numericalvalues of the fifth and sixth forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets620 and 640.

A powertrain 710, shown in FIG. 8a, has the conventional engine andtorque converter 12, a planetary transmission 714, and the conventionalfinal drive mechanism 16. The engine and torque converter 12 aredrivingly connected with the planetary transmission 714 through theinput shaft 17. The planetary transmission 714 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 714 includes a planetary gear arrangement 718that has a first planetary gear set 720, a second planetary gear set730, and a third planetary gear set 740.

The planetary gear set 720 includes a sun gear member 722, a ring gearmember 724, and a planet carrier assembly 726. The planet carrierassembly 726 includes a plurality of pinion gears 727 rotatably mountedon a carrier member 729 and disposed in meshing relationship with boththe sun gear member 722 and the ring gear member 724.

The planetary gear set 730 includes a sun gear member 732, a ring gearmember 734, and a planet carrier assembly member 736. The planet carrierassembly member 736 includes a plurality of pinion gears 737 rotatablymounted on a carrier member 739 and disposed in meshing relationshipwith both the sun gear member 732 and the ring gear member 734.

The planetary gear set 740 includes a sun gear member 742, a ring gearmember 744, and a planet carrier assembly member 746. The planet carrierassembly member 746 includes a plurality of pinion gears 747 rotatablymounted on a carrier member 749 and disposed in meshing relationshipwith both the sun gear member 742 and the ring gear member 744.

The planetary gear arrangement 718 also includes six torque-transmittingmechanisms 750, 752, 754, 756, 758 and 759. The torque-transmittingmechanisms 750, 752, 754 and 756 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 758 and 759 are of the rotating-typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 736, and the output shaft 19 is continuously connectedwith the ring gear member 744. The sun gear member 722 is continuouslyconnected with the planet carrier assembly member 736 through theinterconnecting member 770. The ring gear member 724 is continuouslyconnected with the sun gear member 742 through the interconnectingmember 772. The ring gear member 734 is continuously connected with theplanet carrier assembly member 746 through the interconnecting member774.

The ring gear member 724 is selectively connectable with thetransmission housing 760 through the brake 750. The planet carrierassembly member 726 is selectively connectable with the transmissionhousing 760 through the brake 752. The sun gear member 732 isselectively connectable with the transmission housing 760 through thebrake 754. The planet carrier assembly member 746 is selectivelyconnectable with the transmission housing 760 through the brake 756. Thesun gear member 722 is selectively connectable with the planet carrierassembly member 726 through the clutch 758. The planet carrier assemblymember 726 is selectively connectable with the ring gear member 734through the clutch 759.

The truth table of FIG. 8b defines the torque-transmitting mechanismengagement sequence utilized for each of the forward speed ratios andthe reverse speed ratio. Also given in the truth table is a set ofnumerical values that are attainable with the present inventionutilizing the ring gear/sun gear tooth ratios given in FIG. 8b. TheR1/S1 value is the tooth ratio of the planetary gear set 720; the R2/S2value is the tooth ratio of the planetary gear set 730; and the R3/S3value is the tooth ratio of the planetary gear set 740. As can also bedetermined from the truth table of FIG. 8b, the single step forwardinterchanges are single transition shifts, as are the double stepinterchanges in the forward direction.

FIG. 8b also provides a chart of the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is1.85. Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 740. The numerical values ofthe first and second forward speed ratios are determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 720 and 740.The numerical value of the third forward speed ratio is 1. The numericalvalues of the fourth and seventh forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets720, 730 and 740. The numerical values of the fifth and sixth forwardspeed ratios are determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 730 and 740.

A powertrain 810, shown in FIG. 9a, has the conventional engine andtorque converter 12, a planetary transmission 814, and the final drivemechanism 16. The engine and torque converter 12 are drivingly connectedwith the planetary transmission 814 through the input shaft 17. Theplanetary transmission 814 is drivingly connected with the final drivemechanism 16 through the output shaft 19. The planetary transmission 814includes a planetary gear arrangement 818 that has a first planetarygear set 820, a second planetary gear set 830, and a third planetarygear set 840.

The planetary gear set 820 includes a sun gear member 822, a ring gearmember 824, and a planet carrier assembly 826. The planet carrierassembly 826 includes a plurality of pinion gears 827 rotatably mountedon a carrier member 829 and disposed in meshing relationship with boththe sun gear member 822 and the ring gear member 824.

The planetary gear set 830 includes a sun gear member 832, a ring gearmember 834, and a planet carrier assembly member 836. The planet carrierassembly member 836 includes a plurality of pinion gears 837 rotatablymounted on a carrier member 839 and disposed in meshing relationshipwith both the sun gear member 832 and the ring gear member 834.

The planetary gear set 840 includes a sun gear member 842, a ring gearmember 844, and a planet carrier assembly member 846. The planet carrierassembly member 846 includes a plurality of pinion gears 847 rotatablymounted on a carrier member 849 and disposed in meshing relationshipwith both the sun gear member 842 and the ring gear member 844.

The planetary gear arrangement 818 also includes six torque-transmittingmechanisms 850, 852, 854, 856, 858 and 859. The torque-transmittingmechanisms 850, 852, 854 and 856 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 858 and 859 are of the rotating-typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member842, and the output shaft 19 is continuously connected with the ringgear member 824. The planet carrier assembly member 826 is continuouslyconnected with the planet carrier assembly member 836 through theinterconnecting member 870. The sun gear member 822 is continuouslyconnected with the ring gear member 844 through the interconnectingmember 872. The ring gear member 834 is continuously connected with theplanet carrier assembly member 846 through the interconnecting member874.

The planet carrier assembly member 826 is selectively connectable withthe transmission housing 860 through the brake 850. The ring gear member844 is selectively connectable with the transmission housing 860 throughthe brake 852. The sun gear member 832 is selectively connectable withthe transmission housing 860 through the brake 854. The planet carrierassembly member 846 is selectively connectable with the transmissionhousing 860 through the brake 856. The planet carrier assembly member836 is selectively connectable with the sun gear member 842 through theclutch 858. The sun gear member 842 is selectively connectable with theplanet carrier assembly member 846 through the clutch 859.

The truth table shown in FIG. 9b defines the torque-transmittingmechanism engagement sequence that provides the reverse ratio and sevenforward speed ratios shown in the truth table and available with theplanetary gear arrangement 818. The truth table indicates that thetorque-transmitting mechanism 850 can remain engaged through the neutralcondition, thereby simplifying the forward/reverse interchange. A sampleof numerical values for the individual ratios is also given in the truthtable of FIG. 9b. These numerical values have been calculated using thering gear/sun gear tooth ratios also given by way of example in FIG. 9b.The R1/S1 value is the tooth ratio of the planetary gear set 820; theR2/S2 value is the tooth ratio of the planetary gear set 830; and theR3/S3 value is the tooth ratio of the planetary gear set 840. It can bereadily recognized from the truth table that all of the single anddouble step forward interchanges are single transition ratiointerchanges. FIG. 9b also describes the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is1.63.

Those skilled in the art of planetary transmissions will recognize thatthe numerical values of the reverse and sixth forward speed ratios aredetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 820. The numerical values of the first and seventh forwardspeed ratios are determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 820 and 840. The numerical values ofthe second and fourth forward speed ratios are determined utilizing thering gear/sun gear tooth ratios of the planetary gear sets 820, 830 and840. The numerical value of the third forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets820 and 830. The numerical value of the fifth forward speed ratio is 1.

The powertrain 910, shown in FIG. 10a, includes the conventional engineand torque converter 12, a planetary transmission 914, and theconventional final drive mechanism 16. The engine and torque converter12 are drivingly connected with the planetary transmission 914 throughthe input shaft 17. The planetary transmission 914 is drivinglyconnected with the final drive mechanism 16 through the output shaft 19.The planetary transmission 914 includes a planetary gear arrangement 918that has a first planetary gear set 920, a second planetary gear set930, and a third planetary gear set 940.

The planetary gear set 920 includes a sun gear member 922, a ring gearmember 924, and a planet carrier assembly 926. The planet carrierassembly 926 includes a plurality of pinion gears 927 that are rotatablymounted on a carrier member 929 and disposed in meshing relationshipwith the sun gear member 922 and the ring gear member 924, respectively.

The planetary gear set 930 includes a sun gear member 932, a ring gearmember 934, and a planet carrier assembly member 936. The planet carrierassembly member 936 includes a plurality of pinion gears 937 rotatablymounted on a carrier member 939 and disposed in meshing relationshipwith both the sun gear member 932 and the ring gear member 934.

The planetary gear set 940 includes a sun gear member 942, a ring gearmember 944, and a planet carrier assembly member 946. The planet carrierassembly member 946 includes a plurality of pinion gears 947 rotatablymounted on a carrier member 949 and disposed in meshing relationshipwith both the sun gear member 942 and the ring gear member 944.

The planetary gear arrangement 918 also includes six torque-transmittingmechanisms 950, 952, 954, 956, 958 and 959. The torque-transmittingmechanisms 950, 952, 954 and 956 are stationary-type torque-transmittingmechanisms, commonly termed brakes or reaction clutches. Thetorque-transmitting mechanisms 958 and 959 are of the rotating-typetorque-transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 926, and the output shaft 19 is continuously connectedwith the planet carrier assembly member 946. The planet carrier assemblymember 926 is continuously connected with the ring gear member 934through the interconnecting member 970. The sun gear member 922 iscontinuously connected with the ring gear member 944 through theinterconnecting member 972. The sun gear member 932 is continuouslyconnected with the sun gear member 942 through the interconnectingmember 974.

The sun gear member 922 is selectively connectable with the transmissionhousing 960 through the brake 950. The ring gear member 924 isselectively connectable with the transmission housing 960 through thebrake 952. The planet carrier assembly member 936 is selectivelyconnectable with the transmission housing 960 through the brake 954. Thesun gear member 942 is selectively connectable with the transmissionhousing 960 through the brake 956. The ring gear member 934 isselectively connectable with the sun gear member 932 through the clutch958. The planet carrier assembly member 936 is selectively connectablewith the ring gear member 924 through the clutch 959.

The truth table of FIG. 10b describes the torque-transmitting mechanismengagement sequence utilized to provide the reverse speed ratio andseven forward speed ratios. The truth table also provides a set ofexamples for the ratios for each of the reverse and forward speedratios. These numerical values have been determined utilizing the ringgear/sun gear tooth ratios given in FIG. 10b. The R1/S1 value is thetooth ratio of the planetary gear set 920; the R2/S2 value is the toothratio of the planetary gear set 930; and the R3/S3 value is the toothratio of the planetary gear set 940. It can also be determined from thetruth table of FIG. 10b that each of the forward single step ratiointerchanges are of the single transition variety, as are the doublestep interchanges.

Those skilled in the art, upon reviewing the engagement combinations,will recognize that the numerical value of the reverse speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 930 and 940. The numerical value of the firstforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 940. The numerical values of the second,fourth and fifth forward speed ratios are determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 920, 930 and 940.The numerical value of the third forward speed ratio is 1. The numericalvalues of the sixth and seventh forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear sets920 and 940.

A powertrain 1010, shown in FIG. 11a, includes the conventional engineand torque converter 12, a planetary transmission 1014, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1014 through theinput shaft 17. The planetary transmission 1014 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1014 includes a planetary gear arrangement 1018that has a first planetary gear set 1020, a second planetary gear set1030, and a third planetary gear set 1040.

The planetary gear set 1020 includes a sun gear member 1022, a ring gearmember 1024, and a planet carrier assembly 1026. The planet carrierassembly 1026 includes a plurality of pinion gears 1027 rotatablymounted on a carrier member 1029 and disposed in meshing relationshipwith both the sun gear member 1022 and the ring gear member 1024.

The planetary gear set 1030 includes a sun gear member 1032, a ring gearmember 1034, and a planet carrier assembly member 1036. The planetcarrier assembly member 1036 includes a plurality of pinion gears 1037rotatably mounted on a carrier member 1039 and disposed in meshingrelationship with both the sun gear member 1032 and the ring gear member1034.

The planetary gear set 1040 includes a sun gear member 1042, a ring gearmember 1044, and a planet carrier assembly member 1046. The planetcarrier assembly member 1046 includes a plurality of pinion gears 1047rotatably mounted on a carrier member 1049 and disposed in meshingrelationship with both the sun gear member 1042 and the ring gear member1044.

The planetary gear arrangement 1018 also includes sixtorque-transmitting mechanisms 1050, 1052, 1054, 1056, 1058 and 1059.The torque-transmitting mechanisms 1050, 1052 and 1054 arestationary-type torque-transmitting mechanisms, commonly termed brakesor reaction clutches. The torque-transmitting mechanisms 1056, 1058 and1059 are of the rotating-type torque-transmitting mechanisms, commonlytermed clutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 1026, and the output shaft 19 is continuously connectedwith the ring gear member 1044. The sun gear member 1022 is continuouslyconnected with the sun gear member 1032 through the interconnectingmember 1070. The ring gear member 1024 is continuously connected withthe planet carrier assembly member 1046 through the interconnectingmember 1072. The ring gear member 1034 is continuously connected withthe ring gear member 1044 through the interconnecting member 1074.

The sun gear member 1022 is selectively connectable with thetransmission housing 1060 through the brake 1050. The ring gear member1024 is selectively connectable with the transmission housing 1060through the brake 1052. The sun gear member 1042 is selectivelyconnectable with the transmission housing 1060 through the brake 1054.The ring gear member 1024 is selectively connectable with the planetcarrier assembly member 1036 through the clutch 1056. The planet carrierassembly member 1046 is selectively connectable with the sun gear member1042 through the clutch 1058. The planet carrier assembly member 1026 isselectively connectable with the planet carrier assembly member 1036through the clutch 1059.

The truth table shown in FIG. 11b describes the engagement combinationsand the engagement sequence necessary to provide the reverse drive ratioand the eight forward speed ratios. A sample of the numerical values forthe ratios is also provided in the truth table of FIG. 11b. These valuesare determined utilizing the ring gear/sun gear tooth ratios also givenin FIG. 11b. The R1/S1 value is the tooth ratio for the planetary gearset 1020; the R2/S2 value is the tooth ratio for the planetary gear set1030; and the R3/S3 value is the tooth ratio for the planetary gear set1040. Also given in FIG. 11b is a chart describing the step ratiosbetween the adjacent forward speed ratios and the reverse to firstforward speed ratio.

Those skilled in the art will recognize that the numerical values of thereverse, first and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1020 and1030. The numerical values of the second and eighth forward speed ratiosare determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1020, 1030 and 1040. The numerical value of thethird forward speed ratio is 1. The numerical value of the fourthforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1030. The numerical value of the fifthforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1020. The numerical value of the seventhforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 1020 and 1040.

A powertrain 1110, shown in FIG. 12a, has a conventional engine andtorque converter 12, a planetary transmission 1114, and the conventionalfinal drive mechanism 16. The planetary transmission 1114 includes aplanetary gear arrangement 1118 which is connected with the engine andtorque converter 12 through the input shaft 17 and with the final drivemechanism 16 through the output shaft 19. The planetary gear arrangement1118 includes three planetary gear sets 1120, 1130 and 1140.

The planetary gear set 1120 includes a sun gear member 1122, a ring gearmember 1124, and a planet carrier assembly 1126. The planet carrierassembly 1126 includes a plurality of pinion gears 1127 rotatablymounted on a carrier member 1129 and disposed in meshing relationshipwith both the sun gear member 1122 and the ring gear member 1124.

The planetary gear set 1130 includes a sun gear member 1132, a ring gearmember 1134, and a planet carrier assembly member 1136. The planetcarrier assembly member 1136 includes a plurality of intermeshing piniongears 1137 that are rotatably mounted on a carrier member 1139 anddisposed in meshing relationship with both the sun gear member 1132 andthe ring gear member 1134.

The planetary gear set 1140 includes a sun gear member 1142, a ring gearmember 1144, and a planet carrier assembly member 1146. The planetcarrier assembly member 1146 includes a plurality of pinion gears 1147rotatably mounted on a carrier member 1149 and disposed in meshingrelationship with both the sun gear member 1142 and the ring gear member1144.

The planetary gear arrangement 1118 also includes sixtorque-transmitting mechanisms 1150, 1152, 1154, 1156, 1158 and 1159.The torque-transmitting mechanisms 1150, 1152 and 1154 arestationary-type torque-transmitting mechanisms, commonly termed brakesor reaction clutches. The torque-transmitting mechanisms 1156, 1158 and1159 are of the rotating-type torque-transmitting mechanisms, commonlytermed clutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 1136, and the output shaft 19 is continuously connectedwith the ring gear member 1124. The sun gear member 1122 is continuouslyconnected with the sun gear member 1132 through the interconnectingmember 1170. The ring gear member 1124 is continuously connected withthe ring gear member 1144 through the interconnecting member 1172. Thering gear member 1134 is continuously connected with the planet carrierassembly member 1146 through the interconnecting member 1174.

The sun gear member 1132 is selectively connectable with thetransmission housing 1160 through the brake 1150. The planet carrierassembly member 1146 is selectively connectable with the transmissionhousing 1160 through the brake 1152. The sun gear member 1142 isselectively connectable with the transmission housing 1160 through thebrake 1154. The ring gear member 1144 is selectively connectable withthe planet carrier assembly member 1146 through the clutch 1156. Theplanet carrier assembly member 1126 is selectively connectable with theplanet carrier assembly member 1136 through the clutch 1158. The planetcarrier assembly member 1126 is selectively connectable with the ringgear member 1134 through the clutch 1159.

The truth table shown in FIG. 12b describes the engagement sequence andengagement combinations utilized with the present family member toprovide a reverse drive ratio and eight forward speed ratios. The truthtable of FIG. 12b also provides a set of example numbers that can beestablished in the planetary gear arrangement 1118 utilizing the ringgear/sun gear tooth ratios. The R1/S1 value is the ring gear/sun geartooth ratio of the planetary gear set 1120; the R2/S2 value is the ringgear/sun gear tooth ratio of the planetary gear set 1130; and the R3/S3value is the ring gear/sun gear tooth ratio of the planetary gear set1140.

The chart of FIG. 12b describes the ratio steps between adjacent forwardspeed ratios for an eight-speed transmission. These step ratios areestablished utilizing the example speed ratios given in the truth table.As also shown in the truth table, the torque-transmitting mechanism 1152can remain engaged through the neutral condition, thereby simplifyingthe forward/reverse interchange.

Those skilled in the art will recognize that the numerical values of thereverse, first and sixth forward speed ratios are determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1120 and1130. The numerical values of the second and eighth forward speed ratiosare determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1120, 1130 and 1140. The numerical value of thethird forward speed ratio is 1. The numerical value of the fourthforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1120. The numerical value of the fifthforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1130. The numerical value of the seventhforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 1130 and 1140.

A powertrain 1210, shown in FIG. 13a, includes the conventional engineand torque converter 12, a planetary transmission 1214, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1214 through theinput shaft 17. The planetary transmission 1214 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1214 includes a planetary gear arrangement 1218that has a first planetary gear set 1220, a second planetary gear set1230, and a third planetary gear set 1240.

The planetary gear set 1220 includes a sun gear member 1222, a ring gearmember 1224, and a planet carrier assembly 1226. The planet carrierassembly 1226 includes a plurality of pinion gears 1227 rotatablymounted on a carrier member 1229 and disposed in meshing relationshipwith both the sun gear member 1222 and the ring gear member 1224.

The planetary gear set 1230 includes a sun gear member 1232, a ring gearmember 1234, and a planet carrier assembly member 1236. The planetcarrier assembly member 1236 includes a plurality of pinion gears 1237rotatably mounted on a carrier member 1239 and disposed in meshingrelationship with both the sun gear member 1232 and the ring gear member1234.

The planetary gear set 1240 includes a sun gear member 1242, a ring gearmember 1244, and a planet carrier assembly member 1246. The planetcarrier assembly member 1246 includes a plurality of pinion gears 1247rotatably mounted on a carrier member 1249 and disposed in meshingrelationship with both the sun gear member 1242 and the ring gear member1244.

The planetary gear arrangement 1218 also includes six torquetransmitting mechanisms 1250, 1252, 1254, 1256, 1258 and 1259. Thetorque transmitting mechanisms 1250, 1252 and 1254 are stationary-typetorque-transmitting mechanisms, commonly termed brakes or reactionclutches. The torque-transmitting mechanisms 1256, 1258 and 1259 arerotating type torque transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the sun gear member1242, and the output shaft 19 is continuously connected with the ringgear member 1224. The planet carrier assembly member 1226 iscontinuously connected with the planet carrier assembly member 1236through the interconnecting member 1270. The sun gear member 1222 iscontinuously connected with the ring gear member 1244 through theinterconnecting member 1272. The ring gear member 1234 is continuouslyconnected with the planet carrier assembly member 1246 through theinterconnecting member 1274.

The planet carrier assembly member 1226 is selectively connectable withthe transmission housing 1260 through the brake 1250. The ring gearmember 1244 is selectively connectable with the transmission housing1260 through the brake 1252. The sun gear member 1232 is selectivelyconnectable with the transmission housing 1260 through the brake 1254.The sun gear member 1222 is selectively connectable with the planetcarrier assembly member 1226 through the clutch 1256. The planet carrierassembly member 1236 is selectively connectable with the sun gear member1242 through the clutch 1258. The planet carrier assembly member 1246 isselectively connectable with the sun gear member 1242 through the clutch1259.

The truth table shown in FIG. 13b describes the engagement combinationsand the engagement sequence necessary to provide the reverse drive ratioand the seven forward speed ratios. A sample of the numerical values forthe ratios is also provided in the truth table of FIG. 13b. These valuesare determined utilizing the ring gear/sun gear tooth ratios also givenin FIG. 13b. The R1/S1 value is the tooth ratio for the planetary gearset 1220; the R2/S2 value is the tooth ratio for the planetary gear set1230; and the R3/S3 value is the tooth ratio for the planetary gear set1240. Also given in FIG. 13b is a chart describing the step ratiosbetween the adjacent forward speed ratios and the reverse to firstforward speed ratio.

Those skilled in the art will recognize that the numerical values of thereverse and seventh forward speed ratios are determined utilizing thering gear/sun gear tooth ratio of the planetary gear set 1220. Thenumerical value of the first forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1220 and1240. The numerical values of the second and fifth forward speed ratiosare determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1220, 1230 and 1240. The numerical value of thethird forward speed ratio is determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 1230 and 1240. The numericalvalue of the fourth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 1220 and 1230. Thenumerical value of the sixth forward speed ratio is 1.

A powertrain 1310, shown in FIG. 14a, includes the conventional engineand torque converter 12, a planetary transmission 1314, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1314 through theinput shaft 17. The planetary transmission 1314 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1314 includes a planetary gear arrangement 1318that has a first planetary gear set 1320, a second planetary gear set1330, and a third planetary gear set 1340.

The planetary gear set 1320 includes a sun gear member 1322, a ring gearmember 1324, and a planet carrier assembly 1326. The planet carrierassembly 1326 includes a plurality of pinion gears 1327 rotatablymounted on a carrier member 1329 and disposed in meshing relationshipwith both the sun gear member 1322 and the ring gear member 1324.

The planetary gear set 1330 includes a sun gear member 1332, a ring gearmember 1334, and a planet carrier assembly member 1336. The planetcarrier assembly member 1336 includes a plurality of pinion gears 1337rotatably mounted on a carrier member 1339 and disposed in meshingrelationship with both the sun gear member 1332 and the ring gear member1334.

The planetary gear set 1340 includes a sun gear member 1342, a ring gearmember 1344, and a planet carrier assembly member 1346. The planetcarrier assembly member 1346 includes a plurality of pinion gears 1347rotatably mounted on a carrier member 1349 and disposed in meshingrelationship with both the sun gear member 1342 and the ring gear member1344.

The planetary gear arrangement 1318 also includes six torquetransmitting mechanisms 1350, 1352, 1354, 1356, 1358 and 1359. Thetorque transmitting mechanisms 1350, 1352 and 1354 are stationary-typetorque transmitting mechanisms, commonly termed brakes or reactionclutches. The torque transmitting mechanisms 1356, 1358 and 1359 arerotating-type torque transmitting mechanisms, commonly termed clutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 1336, and the output shaft 19 is continuously connectedwith the ring gear member 1324. The sun gear member 1322 is continuouslyconnected with the sun gear member 1332 through the interconnectingmember 1370. The ring gear member 1324 is continuously connected withthe ring gear member 1344 through the interconnecting member 1372. Thering gear member 1334 is continuously connected with the planet carrierassembly member 1346 through the interconnecting member 1374.

The sun gear member 1332 is selectively connectable with thetransmission housing 1360 through the brake 1350. The planet carrierassembly member 1346 is selectively connectable with the transmissionhousing 1360 through the brake 1352. The sun gear member 1342 isselectively connectable with the transmission housing 1360 through thebrake 1354. The planet carrier assembly member 1326 is selectivelyconnectable with the planet carrier assembly member 1336 through theclutch 1356. The planet carrier assembly member 1336 is selectivelyconnectable with the sun gear member 1342 through the clutch 1358. Thesun gear member 1342 is selectively connectable with the planet carrierassembly member 1346 through the clutch 1359.

The truth table shown in FIG. 14b describes the engagement combinationsand the engagement sequence necessary to provide the reverse drive ratioand the seven forward speed ratios. A sample of the numerical values forthe ratios is also provided in the truth table of FIG. 14b. These valuesare determined utilizing the ring gear/sun gear tooth ratios also givenin FIG. 14b. The R1/S1 value is the tooth ratio for the planetary gearset 1320; the R2/S2 value is the tooth ratio for the planetary gear set1330; and the R3/S3 value is the tooth ratio for the planetary gear set1340. Also given in FIG. 14b is a chart describing the step ratiosbetween the adjacent forward speed ratios and the reverse to firstforward speed ratio.

Those skilled in the art will recognize that the numerical value of thereverse speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 1340. The numerical value of the firstforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 1320 and 1330. The numerical value ofthe second forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1320, 1330 and 1340. Thenumerical value of the third forward speed ratio is 1. The numericalvalue of the fourth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 1320. The numericalvalue of the fifth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 1330. The numericalvalues of the sixth and seventh forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1330 and 1340.

A powertrain 1410, shown in FIG. 15a, includes the conventional engineand torque converter 12, a planetary transmission 1414, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1414 through theinput shaft 17. The planetary transmission 1414 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1414 includes a planetary gear arrangement 1418that has a first planetary gear set 1420, a second planetary gear set1430, and a third planetary gear set 1440.

The planetary gear set 1420 includes a sun gear member 1422, a ring gearmember 1424, and a planet carrier assembly 1426. The planet carrierassembly 1426 includes a plurality of pinion gears 1427 rotatablymounted on a carrier member 1429 and disposed in meshing relationshipwith both the sun gear member 1422 and the ring gear member 1424.

The planetary gear set 1430 includes a sun gear member 1432, a ring gearmember 1434, and a planet carrier assembly member 1436. The planetcarrier assembly member 1436 includes a plurality of pinion gears 1437and 1438 rotatably mounted on a carrier member 1439 and disposed inmeshing relationship with both the sun gear member 1432 and the ringgear member 1434.

The planetary gear set 1440 includes a sun gear member 1442, a ring gearmember 1444, and a planet carrier assembly member 1446. The planetcarrier assembly member 1446 includes a plurality of pinion gears 1447and 1448 rotatably mounted on a carrier member 1449 and disposed inmeshing relationship with both the sun gear member 1442 and the ringgear member 1444.

The planetary gear arrangement 1418 also includes six torquetransmitting mechanisms 1450, 1452, 1454, 1456, 1458 and 1459. Thetorque transmitting mechanisms 1450, 1452, 1454 and 1456 arestationary-type torque transmitting mechanisms, commonly termed brakesor reaction clutches. The torque transmitting mechanisms 1458 and 1459are rotating type torque transmitting mechanisms, commonly termedclutches.

The input shaft 17 is continuously connected with the planet carrierassembly member 1426, and the output shaft 19 is continuously connectedwith the ring gear member 1444. The planet carrier assembly member 1426is continuously connected with the planet carrier assembly member 1436through the interconnecting member 1470. The sun gear member 1422 iscontinuously connected with the planet carrier assembly member 1446through the interconnecting member 1472. The sun gear member 1432 iscontinuously connected with the sun gear member 1442 through theinterconnecting member 1474.

The sun gear member 1422 is selectively connectable with thetransmission housing 1460 through the brake 1450. The ring gear member1424 is selectively connectable with the transmission housing 1460through the brake 1452. The ring gear member 1434 is selectivelyconnectable with the transmission housing 1460 through the brake 1454.The sun gear member 1442 is selectively connectable with thetransmission housing 1460 through the brake 1456. The planet carrierassembly member 1436 is selectively connectable with the sun gear member1432 through the clutch 1458. The ring gear member 1424 is selectivelyconnectable with the ring gear member 1434 through the clutch 1459.

The truth table shown in FIG. 15b describes the engagement combinationsand the engagement sequence necessary to provide the reverse drive ratioand the seven forward speed ratios. A sample of the numerical values forthe ratios is also provided in the truth table of FIG. 15b. These valuesare determined utilizing the ring gear/sun gear tooth ratios also givenin FIG. 15b. The R1/S1 value is the tooth ratio for the planetary gearset 1420; the R2/S2 value is the tooth ratio for the planetary gear set1430; and the R3/S3 value is the tooth ratio for the planetary gear set1440. Also given in FIG. 15b is a chart describing the step ratiosbetween the adjacent forward speed ratios and the reverse to firstforward speed ratio.

One skilled in the art will recognize that the numerical value of thereverse speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 1430 and 1440. The numerical value ofthe first forward speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 1440. The numerical values ofthe second, fourth and fifth forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1420, 1430 and 1440. The numerical value of the third forward speedratio is 1. The numerical values of the sixth and seventh forward speedratios are determined utilizing the ring gear/sun gear tooth ratios ofthe planetary gear sets 1420 and 1440.

While the best modes for carrying out the invention have been describedin detail, those familiar with the art to which this invention relateswill recognize various alternative designs and embodiments forpracticing the invention within the scope of the appended claims.

What is claimed is:
 1. A multi-speed-transmission comprising: an inputshaft; an output shaft; first, second and third planetary gear sets eachhaving first, second and third members; said input shaft beingcontinuously interconnected with at least one member of said planetarygear sets, said output shaft being continuously interconnected withanother member of said planetary gear sets; a first interconnectingmember continuously interconnecting said first member of said firstplanetary gear set with said first member of said second planetary gearset; a second interconnecting member continuously interconnecting saidsecond member of said first planetary gear set with said first member ofsaid third planetary gear set; a third interconnecting membercontinuously interconnecting said second member of said second planetarygear set with said second member of said third planetary gear set; afirst torque-transmitting mechanism selectively interconnecting astationary transmission housing with a member of said first or secondplanetary gear sets; a second torque-transmitting mechanism selectivelyinterconnecting said stationary transmission housing with a member ofsaid second planetary gear set; a third torque-transmitting mechanismselectively interconnecting a member of said third planetary gear setwith said transmission housing; a fourth torque-transmitting mechanismselectively interconnecting a member of said first planetary gear setwith another member of said planetary gear sets; a fifthtorque-transmitting mechanism selectively interconnecting a member ofsaid second planetary gear set with another member of said planetarygear sets; and a sixth torque-transmitting mechanism selectivelyinterconnecting a member of said third planetary gear-set with anothermember of said planetary gear sets or with said transmission housing,said members interconnected by said sixth torque-transmitting mechanismbeing different from the members interconnected by said first, second,third, fourth and fifth torque-transmitting mechanisms; said membersinterconnected by said first, second and third torque-transmittingmechanisms being different from the members continuously interconnectedwith said input shaft and said output shaft; said torque-transmittingmechanisms being engaged in combinations of two to establish at leastseven forward speed ratios and a reverse speed ratio between said inputshaft and said output shaft.
 2. The multi-speed transmissions defined inclaim 1, wherein said first, second and third torque-transmittingmechanisms comprise brakes.
 3. The multi-speed transmissions defined inclaim 1, wherein said fourth, fifth and sixth torque-transmittingmechanisms comprise clutches.
 4. The multi-speed transmissions definedin claim 1, wherein said sixth torque-transmitting mechanism comprises aclutch selectively interconnecting a member of said third planetary gearset with another member of said planetary gear sets.
 5. The transmissiondefined in claim 1, wherein said sixth torque-transmitting mechanismcomprises a brake selectively interconnecting a member of said thirdplanetary gear set with said transmission housing.
 6. A multi-speedtransmission comprising: an input shaft; an output shaft; a planetarygear arrangement having first, second and third planetary gear sets,each planetary gear set having first, second and third members; saidinput shaft being continuously interconnected with at least one memberof said planetary gear sets, said output shaft being continuouslyinterconnected with another member of said planetary gear sets; a firstinterconnecting member continuously interconnecting said first member ofsaid first planetary gear set with said first member of said secondplanetary gear set; a second interconnecting member continuouslyinterconnecting said second member of said first planetary gear set withsaid first member of said third planetary gear set; a thirdinterconnecting member continuously interconnecting said second memberof said second planetary gear set with said second member of said thirdplanetary gear set; and six selectively engageable torque-transmittingmechanisms for selectively interconnecting said members of saidplanetary gear sets and said transmission housing in combinations of twoto establish at least seven forward speed ratios and one reverse speedratio between said input shaft and said output shaft.
 7. Thetransmission defined in claim 6, wherein a first of said sixtorque-transmitting mechanisms is operable for selectivelyinterconnecting said stationary transmission housing with a member ofsaid first or second planetary gear sets.
 8. The transmission defined inclaim 6, wherein a second of said six torque-transmitting mechanisms isoperable for selectively interconnecting said stationary transmissionhousing with a member of said second planetary gear sets.
 9. Thetransmission defined in claim 6, wherein a third of said sixtorque-transmitting mechanisms is selectively operable forinterconnecting a member of said third planetary gear set with saidtransmission housing.
 10. The transmission defined in claim 6, wherein afourth of said six torque-transmitting mechanisms is selectivelyoperable for interconnecting a member of said first planetary gear setwith another member of said planetary gear sets.
 11. The transmissiondefined in claim 6, wherein a fifth of said six torque-transmittingmechanisms is selectively operable for interconnecting a member of saidsecond planetary gear set with another member of said third planetarygear sets.
 12. The transmission defined in claim 6, wherein a sixth ofsaid six torque-transmitting mechanisms selectively interconnects amember of said third planetary gear set with another member of saidplanetary gear sets or with said transmission housing.
 13. Thetransmission defined in claim 6, wherein planet carrier assembly membersof each of said planetary gear sets are of the single-pinion type. 14.The transmission defined in claim 6, wherein at least one planet carrierassembly member of said planetary gear sets is of the double-piniontype.
 15. A multi-speed transmission comprising: an input shaft; anoutput shaft; first, second and third planetary gear sets each havingfirst, second and third members; said input shaft being continuouslyinterconnected with at least one member of said planetary gear sets,said output shaft being continuously interconnected with another memberof said planetary gear sets; a first interconnecting member continuouslyinterconnecting said first member of said first planetary gear set withsaid first member of said second planetary gear set; a secondinterconnecting member continuously interconnecting said second memberof said first planetary gear set with said first member of said thirdplanetary gear set; a third interconnecting member continuouslyinterconnecting said second member of said second planetary gear setwith said second member of said third planetary gear set; first, second,third, fourth, fifth and sixth torque-transmitting mechanismsselectively engageable in pairs to establish combinations of membersjoined for common rotation to provide at least seven forward speedratios and a reverse speed ratio between said input shaft and saidoutput shaft, said combinations including either: an engaged combinationwith said first torque-transmitting mechanism selectivelyinterconnecting said first member of said first planetary gear set withsaid transmission housing, said second torque-transmitting mechanismselectively interconnecting said second member of said second planetarygear set with said transmission housing, said third torque-transmittingmechanism selectively interconnecting said first member of said thirdplanetary gear set with said transmission housing, said fourthtorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said third member of saidthird planetary gear set, said fifth torque-transmitting mechanismselectively interconnecting said third member of said second planetarygear set with said third member of said third planetary gear set, andsaid sixth torque-transmitting mechanism selectively interconnectingsaid third member of said third planetary gear set with said secondmember of said third planetary gear set; or an engaged combination withsaid first torque-transmitting mechanism selectively interconnectingsaid first member of first planetary gear set with said transmissionhousing, said second torque-transmitting mechanism selectivelyinterconnecting said third member of said second planetary gear set withsaid transmission housing, said third torque-transmitting mechanismselectively interconnecting said first member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said third planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said third member of said second planetary gear set withsaid second member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said thirdmember of said third planetary gear set with said second member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid third member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said first member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said second member of said firstplanetary gear set with said second member of said third planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said second member of said second planetary gear setwith said third member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said thirdmember of said second planetary gear set with said third member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid second member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said first member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said first member of said second planetary gear set withsaid third member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said firstmember of said third planetary gear set with said third member of saidsecond planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said secondmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid first member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said third member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said second member of said second planetary gear setwith said third member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said secondmember of said third planetary gear set with said third member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said secondmember of said second planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid third member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said third member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said third member of said second planetary gear set withsaid first member of said third planetary gear set, and sixthtorque-transmitting mechanism selectively interconnecting said thirdmember of said third planetary gear set with said first member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid third member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said third member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said second member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said second member of said second planetary gear setwith said third member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said firstmember of said third planetary gear set with said transmission housing;or an engaged combination with said first torque-transmitting mechanismselectively interconnecting said third member of said first planetarygear set with said transmission housing, said second torque-transmittingmechanism selectively interconnecting said third member of said secondplanetary gear set with said transmission housing, said thirdtorque-transmitting mechanism selectively interconnecting said secondmember of said third planetary gear set with said transmission housing,said fourth torque-transmitting mechanism selectively interconnectingsaid first member of said first planetary gear set with said thirdmember of said first planetary gear set, said fifth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said second member of said second planetary gearset, and said sixth torque-transmitting mechanism selectivelyinterconnecting said first member of said third planetary gear set withsaid transmission housing; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid third member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said second member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said first member of said firstplanetary gear set with said third member of said third planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said third member of said third planetary gear set withsaid second member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said firstmember of said third planetary gear set with said transmission housing;or an engaged combination with said first torque-transmitting mechanismselectively interconnecting said third member of said first planetarygear set with said transmission housing, said second torque-transmittingmechanism selectively interconnecting said third member of said secondplanetary gear set with said transmission housing, said thirdtorque-transmitting mechanism selectively interconnecting said secondmember of said third planetary gear set with said transmission housing,said fourth torque-transmitting mechanism selectively interconnectingsaid third member of said first planetary gear set with said thirdmember of said second planetary gear set, said fifth torque-transmittingmechanism selectively interconnecting said first member of said secondplanetary gear set with said second member of said second planetary gearset, and said sixth torque-transmitting mechanism selectivelyinterconnecting said first member of said third planetary gear set withsaid transmission housing; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said secondmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid first member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said third member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said second member of said first planetary gear set withsaid third member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said firstmember of said third planetary gear set with said third member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid second member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said third member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said second member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said third member of said first planetary gear set withsaid third member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said secondmember of said third planetary gear set with said first member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid third member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said first member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said first member of said firstplanetary gear set with said second member of said first planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said first member of said second planetary gear set withsaid third member of said third planetary gear set, and sixthtorque-transmitting mechanism selectively interconnecting said secondmember of said third planetary gear set with said third member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said firstmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid second member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said third member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said third member of said second planetary gear set withsaid third member of said third planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said secondmember of said third planetary gear set with said third member of saidthird planetary gear set; or an engaged combination with said firsttorque-transmitting mechanism selectively interconnecting said thirdmember of said first planetary gear set with said transmission housing,said second torque-transmitting mechanism selectively interconnectingsaid third member of said second planetary gear set with saidtransmission housing, said third torque-transmitting mechanismselectively interconnecting said second member of said third planetarygear set with said transmission housing, said fourth torque-transmittingmechanism selectively interconnecting said third member of said firstplanetary gear set with said third member of said second planetary gearset, said fifth torque-transmitting mechanism selectivelyinterconnecting said first member of said second planetary gear set withsaid second member of said second planetary gear set, and said sixthtorque-transmitting mechanism selectively interconnecting said firstmember of said third planetary gear set with said transmission housing.